A simple setting change can get you extra brightness on web pages and documents

The Samsung Galaxy S4's Full HD SuperAMOLED screen is the best AMOLED display we've seen on a smartphone. However if you're noticing subpar brightness some of the time, there's an option in "Display settings" you might want to take a look at.

By default, the Galaxy S4 and many other Samsung devices ship with "Auto adjust display tone" turned on. You can find it under Settings > My device > Display > More settings. When enabled, it tweaks the display brightness based on the on-screen image to avoid burning through an excessive amount of juice. Most of the time you might not notice this, but there's an easy way to see its effects.

When there's a lot of white space on-screen, "Auto adjust screen tone" will dim the display slightly to save power. The effect is subtle, but jump between a website like Google in the web browser and your home screen and you'll probably notice that after a split second the page is dimmed slightly. That's good if you want to save power, bad if you want to take full advantage of that big, bright screen.

So if you favor battery life, you can leave it turned on - after all, it's designed to save power. But to get the brightest possible image on your Galaxy S4, you may well want to turn this setting off.